Acceptance + full funding, deadline before I hear back from other schools

I just heard back from a school in Canada (TA + fellowship= full tuition + living) for a masters in urban geography. Great program- I love it (woo hoo!). Problem is that I have to reply ~2 weeks before I'll hear back from my other top choice (US school). Torn between the following options: Call US school asking for an early decision (noting funding etc from other school), accept Canadian school and wait for US school (risk having to retract acceptance which I don't want to do unless absolutely necessary), or ask Canadian school for more time (until the end of March).

Tried to find advice online but to no great avail. Sorry if this has come up in years past!

I don't think it's unreasonable to ask for an extension since April 15th is generally accepted as the decision deadline for US schools. They obviously want you or they wouldn't have made you that offer. With that said, I think you'll be hard pressed to get a better financial offer from the American schools. A US school may cover your tuition but very rarely do they give you enough to sufficiently cover living expenses, particularly for a terminal planning degree.